WASHINGTON - Members of Congress and the Bush administration are at odds over whether security is compromised by an Arab company's takeover of operations at six major American seaports.

Some lawmakers expressed concern Sunday that the safeguards are insufficient to thwart infiltration of the vital facilities by terrorists.

At issue is the purchase last week of London-based Peninsular and Oriental Steam Navigation Co., by Dubai Ports World, a state-owned business in the United Arab Emirates, or UAE. Peninsular and Oriental runs major commercial operations in New York, New Jersey, Baltimore, New Orleans, Miami and Philadelphia.

Homeland Security Secretary Michael Chertoff defended the U.S. security review of DP World in various television interviews Sunday.

"We make sure there are assurances in place, in general, sufficient to satisfy us that the deal is appropriate from a national security standpoint," Chertoff told ABC's "This Week."

The government typically builds in "certain conditions or requirements that the company has to agree to make sure we address the national security concerns," he said on NBC's "Meet the Press," but added that details were classified.

Rep. Peter King (news, bio, voting record), R-N.Y., chairman of the House Homeland Security Committee, said later he wasn't as sure.

"I'm aware of the conditions and they relate entirely to how the company carries out its procedures, but it doesn't go to who they hire, or how they hire people," King told The Associated Press.

"They're better than nothing, but to me they don't address the underlying conditions, which is how are they going to guard against things like infiltration by al-Qaida or someone else? How are they going to guard against corruption?" King said.

Critics have cited the UAE's history as an operational and financial base for the hijackers who carried out the attacks of Sept. 11, 2001. In addition, they contend the UAE was an important transfer point for shipments of smuggled nuclear components sent to Iran, North Korea and Libya by a Pakistani scientist.